1. Field of the Invention
The invention relates to the field of VTOL aircraft, and in particular, to an aircraft which is capable of sustained vertical flight following the loss of thrust from a propulsion unit. This means the continued safe flight following the failure of not only an engine but a gearbox or propeller/rotor.
2. Description of Related Art
The advantages of an aircraft taking off and landing without an airport are obvious. Fixed wing aircraft are restricted to operations from relatively few airports and many of these airports are not their desired destination. In military applications, airbases are vulnerable to attack. The response time of forward positioning of a VTOL support vehicle is significantly reduced and the range requirements are also reduced. Flexible positioning is also valuable in air ambulance applications, where the total response and delivery time “the golden hour” is critical to the survival of the patient.
The pursuit of an aircraft which can take-off and land vertically which possesses the speed, range, and payload capacity of an airplane has continued since the invention of the helicopter.